Combustion-engine.



Ef A. www; CNIBST! ENGINE.' APPUCRHN FELED MN. I3', `905- HENEWED wmv es, 1915,

NEEN-SHEET I.

SPEHYT CMBUSTON ENGNE. APPucJmN man Mm. sa, 1905. www MA/ 6, 1915.

Patented May-15, mi?" 6 SHEETS-SHEET 2.

@mmm .my y', im.

SHEETSMSHEET 3.

i2. A. Smm. Comuslowwww. APPLIJAHQH FILED JAN. 1B, V505.

{ENEWL' MAY i3, 1915.

E. AySPEmIY. CIv'IBUSTION ENGINE. APPLICATION FILED IAII. IB, 1905. RIENEWED MY 6; ISIS.

Mmmm May 15, 191'?.

E SHEETS-SI'IEET 4. .A

E. A. SPERRY.

\ COMBUSTION ENGINE.y

4 APPLICATION FILED JAN. I8, 1905. HENEWED MAY 6,1915. 1,26 ,1% Patented .May 15, 1917.

6 'SHEETS-SHEET 5. i

E. A. SPRRY.

* COMBUSTIGN ENGINE. APPLICATION FILED IAN. III, 1905. IIEIIEIIIED IIIAY 6,1915.

Patented Maly 15, 1917.

6 SHEETS-SHEET 6.

M w W ELMER A. SPERRY, OF BROOKLYN, NEW YORK.

ooMBUsrioN-ENGINE.

nasales.

specineation of Letters Patent.

rammen nay i5, ieri.

Application filed Jamirv ry 18, 1905, Serial No. 241,680. Renewed May 6, 1915. Serial No. 2,424.

To ZZ whom 'it inni/concern Be it knownl that l, llmiica' A. Srniinr, a citizen of the United States, residing at 100 Marlborough road, Brooklyn, in the county of Kings and State of New `York, have invented new and useful Improvements in CombustionEngines, of which the following is a specification.

This invention relates to compound combustion engines operating preferably upon the pre-co1npression four-stroke cycle described in my previous application for Letters Patent No. 454,752, December l01 1892, and wherein after the combustion stroke of the high-pressure cylinder or cylinders the gases are admitted to a low-pressure cylinder of large area, which then takes up the fiir ther expansion lof the gases and carries the same down preferably to or near the atmospheric pressure; and iny invention consists in certain improvements fully set forth hereinafter and which may be carried out in.

various' forms of apparatus, one of which is illustrated'in the accompanying drawing, in wliich- Figure 1 is a side elevation in part section of a four-cycle compound combustion engine embodying my improvements;

Fig. 2 is al plan view; y

Fig. 3 is an enlarged section on the line 3 3, Fig. Q, looking in the direction of the arrow;

Fig. 4 is a section on the line livel, Fig. 2,

i lookingI in thefdirectioii of the arrow,

` Fig. 5 is an enlarged section on line 5 5, Fig. 2, looking in the direction of the arrow;

Fig. (5 is a longitudinal section of the pump illustrating dia grammatically the governi n g system Fig. 7 is a detached view of part of the governing apparatus; K

Figs.` 8, 9,'and l0 are details of construction of parts shown in Fig. 7.

Before describing the principal operations of my apparatus, l will first refer to the construction shown in the drawings, in which the engine has two high-pressure cylinders 1, 2, and a large low-pressure cylinder 3, the

piston of the latter'conn'ected toga crossliead 30, from which a connecting rod eX- tends to one'of the cranks of the-crank shaft 32, while the other crank, at 180 degrees from the first, is connected by a connecting rod 33 with a cross head 34 tovwhich both of the a gas inlet or induction valve 36 at each end 'of the cylinder l, and a cross pipe 37, also communicating with the pipe 6, extends to the induction gas valve casing 35 at each end of the cylinder 2.

An air reservoir 7 adjacent to the gas reservoir 9commiinicates through a pipe 5 with two cross pipes 39, each of which coinl municates at each end with a valve casing40 of an induction valve 41 at each end ofeach ofl the high-pressure cylinders, a port 42 affording a con'imunication between each easing 35 and the adjacent casing 4:0. Each of the aforesaid valves has a stein extending outwardly and provided with a head against which bears a spring 43 which tends to keep the valve upon its seat, and with these valves are arranged any suitable appliance whereby they may be opened at proper times as hereinafter described.' shown, there is combined with the valves of each of the highpressure cylinders l and Q, a shaft 25 earrying cams which operate upon levers 26 and 27 connected by links with levers 28 and 29, that hear upon the stems respectively'of the valves 3G and 4l.

Each cam shaft 25 derives its rotation conductors 6l, 62, springs 63 closing ,theif val vc to its seat, and levers4 64 operated by cams on the cam shafts 25 serving to lift the valves at suitable intervals. The stem 200 of said valve 20 slides in a removable guiding cap 201 located on side of the larger of the two valve seats so that on removal of this" stems of horizontal stem 71 with a head against which ,to its seat, and' a bell crank jupon f i netically oated, that is,

keep the valve lever 7 3 .bears this head rand is operated by the cam on the lower cam shaft 25 through the medium of"a lever 25. lThis valve`islmagbears a spring 72 tending to preferably electroanagnets 74l have their poles above the stem of the valve in such a` manner as to counterbalance as nearly'f'asj possible the weight of `thevalve andprevent the irregular wearing of theyalve andseat at the lower edges,which:` would otherwiseoccur, thereby insuringjas uniform a' wearing o-f the valve and seat as in'Y the case of a horil yzontal valve with avertical stem. Means for adjusting the magnets result isshown in the rheostat 76, Fig. 3,

i suitably connected ,in an electiicciicuit 77 withan electrical supply source.

4 The reservoirs 7 and 9 are preferably long hollow cylinders cross ,/pipe'or cylinder v1() within which floats piston relative pressures within' the cylinders, by

weighting the said piston Vin'on'e directionor i the other. Thlus, as shown, the piston rod Aextends throughpacking boxes in the cylinders in both directionsv 'and Ais 'adapted for connection at either or e 14 passing over a guide pulley 'vided with a suitable number of weights 13.

When itis desired to run thefair at aI Y higher pressure than the gas, the weight is attached to the end of the pistonso as to toA whenit is desired that carry-the latter'toward the air reservoir, and the gas shall be at a higher pressure Ithan the air, the weight is transferred to the opposite'end of the piston rod. "It will be evidentthat other means may 'beifemployed for securing 4a preponder* ance vof pres uredn one reservoir or the -other, as for instance, a pump supplying`A both reservoirs through conduits provided with a weighted valve. The pump E supplies x the two reservoirs .i through suitable conduits-80,V 81, one .end of the. pump cylinder receiving .gas and the other air, and the piston discharging the exhaust valve 22 has a a series of magnets, l

74 to vbring about this.L

and communicate at some- L vpoint between their'ends through the me diuni of 12 for determining the ach end with a cable 15 and pro- -responsive governor G, Fig. 6, vany r'rotating part, as the extremity of one same as it moves in alternate directions to the respective reservoirs, suitable valves beingarranged as shown in Fig. G, and it will be's'een that the air and the gaseous fuel are pumped and stored and delivered separately 7\. from each other, so that there is no combustible mixture present in the apparatusV until the moment when the two gases are brought together at the induction valve orr valves, j

The gas and air pump may be rendered adjustable as to the amount of Huid displaced, and therefore the amount fed to the system, in an suitable manner. In the present instance it hasa variable clearance at 80 each end, that is7 the cubical contents of the clearance space .existing when the piston'is at the end of its stroke may be varied., One

means of securing this result'is a reservoir 82 contains a piston 83 adjustable by -,means of a toothed nut .84 turning on the threaded stem85' of the piston, so that l the dimensions of the vchamber may be reduced, even toa negligible quantity, by

carrying the piston inward, and increased by carrying Iit outward. As one means of` simultaneously `varying the dimensions .of these chambers, I make use of an electric motor M,`preferably` a` reversible motor, the-95 arma-ture .shaft of which. carriespinions 86l gearing with the toothed or' gear. nuts 84,'and to allow for the'indepe'ndent setting ofi; either piston, the pinions l86 are fitted tpv splines v100, of the 'shaft, so as to turn therewith but slide thereon, whereby either may be moved inward anddisconnected from the gear nuts 84 topermit the' latter to be turned to set the pisto-n in vany desired position, after which the pinion 86 is again brought into gear with the gear nut, vbeing maintained in place by a spring 87. The gear nuts' are provided with 4handles 88by means of which hand. As the motor they may be turned by runsl in one direction, the gears and screws operate to reduce the adjustable clearance a number of different methods may be employed to this end. As one method for automatic kcontrol or governing for constant speed, I have illustrated a centrifugal speed- 125 driven from of the cam shafts 25. As the balls move in response. to variations of speed, they raise 'and lower the sleeve 101v and'lever 102, which 180 or angular partsloov equivalent device 1053,'causing themotor lllto run in opposite directions, orto be brought to rest when the device 10S- is open circuited and the leveiI tion.`

A reversiblemovement of great power is thus secured under sensitive and perfect control, either automatic or otherwise, which is readily available for any and all purposes relative to the proper manipulation of the engine parts to secure the desired result.

In Figs. 7 to 10 are shown the variable lift cam 104 upon the cam shaft 25 and also one torni of an igniter timing device 10G tor the electric or other ignition system of the engine. The screw shaft 107 is coupled with the Shaft of motor M so as to rotate therewith by any suitable means, as for instance. a chain 108 and sprockets 109, 110. As the screw shaft 107 revolves, its oppositely threaded ends cause opposite corresponding longitudinal moven'ients of nuts 112, 113, on guides 111, with the connected parts, such as wedges 115 on the collars 110 which sli'de on` the shaft 25. The wedges 115 perform two functions, first that of raising and lowering 102 is in its mid posi- 1 the cam lug 104 against the action of springs 118; and second, by altering the. timing' ofV the spark by means of a lateral inclined face 119 on each wedge shown in FiglO, which serves'to change the lead of the lo( se collar 120, by'coperating with aprojecti n or the like on said collar and turning theI collar against the action of the spring 121 forminoa part of the spark-timing device referred to. The ring 120 .times the ignition spark or flash in any suitable manner, as for inthe'variatlons in richness ot fuel or mixtures stance hy cooperating electrical contacts 122 and 123, the former moving with rthe rin Y 120 and the latter stationary', both these contacts being,` provided with suitable electrical connection to the ignition system of the engine, preferably deriving its energy from a single source S which may be 'of any suit-,

able character or construction, such as a battery, generator, supply mains, &e.

1t will be readily understood that the lead or advancement of the spark, especially tor constant speed, shouldbe adjustable to .meet

or the lquantity used by the engine and which may become desirable from any conditions connected withl the pre-compression or double expansion of the, gases, &c. One means for varying the` richness ot the mixture or quantity used is shown in the variable lift cam 101 which may be used'to control the gas valve or valves 30 or the miking valve or valves 41', as will be readily understood.

, Ingthe construction' above described, it will be seen that the air and the gas are supplied After the reception of the mixture at one end of each otthe high-pressure cylinders, the piston moves trom that end, the val-ves close; as the piston moves back, yeffecting` the con'ipression ot the charge. itis then exploded in the chamber 00, Fig. 3, by means of 'a suitable electric exploder 91, preferably deri ving energy i' rom the same source S as the magnets T-l and other parts, and the high pressure stroke follows. The return stroke after the h igh pressure is the exhaust stroke" ot' the cycle. which isa t'onr stroke one, and is here utilized as the transfer stroke to thellow pressure cylinder during the period when it is delivering its power stroke, the transfer valv'e Q0 reniaining open during this sti-oke. As a result` the low pressure cylinder begins its power stroke at about the terminal pressure oi the gases at the end of the power stroke within the high pressure cylinder, so that there a relatively high pressure dur`-` ingy the power stroke of the high pressure piston and a gradual reduction of pressure in the low pressure cylinder from the termination of this stroke within the high pressure cylinder. which 'falls toatmosphere by the time the low pressure piston reaches the end of its power stroke. The relative ,arrangement ot the two high pressure cylinders is such that each piston moves or operi ates on the 'crank shaft 360 vbehind ,the` other. Thus it will he seen that one transfer valve 20 is held openl during one power stroke oi the low pressure piston andthe other opened during the next, and upon teach return movement of the low pressurepiston its exhaust valve 22 is opened and the spent ,rases are fully discharged through the exhaustpipc 191. thisreturn action of the plston heinoefi'cctcd by th(l Q'ases exhaijlstwly `one and then the other ot' the high pressure?" pistons upon Asuccessive strokes. 'Every stroke in each direction from the low pressure piston is also a power stroke, the pres-l sures upon cach stroke from a given end loeine' supplied altermitely from the high presi" sure cylinders at this cud, all ot' this being brounhtabout through the properrelative arrangement ofthe parts in connection with the two hifrlri'iressure cylinders. Onen'lethod of scavenging the cylinders is secured by arranging the cams of the air inlet` valves ot' the lilgh-pressure cylinder' so as to 2g'lve a slight lead to the air `entrance ahead of the mixture with they y Upon closing these valves, this lead should airunmixed with gas be reversed, the gas valve closing a trifle n head of the air Valve, wliierebythat portion of the casing above the air or admission valve is swept clear of gas and thereby no gas Will mix with the air which stands i'n this reservoir ready to be admitted upon the next opening of the air valve, and thus is secured scavenging.

As before pointed out, the clearance spaces of the high pressure or combustion lcylinder operating under this system are very large and 4it therefore becomes neces-l sary under certain conditions of operation that they be cleared of all'inert gases or to the introduction of the products prior next charge, especially soon account of the extra amount-v of oxygen thus 4rendered Y available for combustion would be otherwise' displaced. .By opening' the air purposes, which valve near the termination of the exhaust stroke the inert gases are swept out of the combustion cylinder and into the low pressure cylinder. This' will lill the clearance space of the combustion cylinder yvith air vyhioh is desirable. Thegas valve is opened subsequently and the gas mixes With the air inthe clearance space and from the 'supplyy to form' the charge, It Will be seenthat in the construction shown, the

- inert gases areswept von into the low-prespre-'compresslon o the. vaporized incl lor gas at anyv suitable Y 'combustin engi-nahen@ .priorte'combus'f... 46

ders and compelled l to -.the.smallerv s ons" 11d-When their pres;

sure' has'v fal en' su ciently. theirjenergy isl..

l utilized "upo'" intended or' necessary stroke of will-be seenthat therelative pressures may A cy -sipation off hat' Memor-4e e cubical'contentsi-than vinv asfenip'llarA engi sure' .cylinder and Whateverv pressure they retain is f fully utilized therein. It is not 4that the displacement air or `any considerable quantity thereofshould enter vthe low-pressure cylinf othersomitted without'i'nterferingivith 'the operation ispreferably vgaged and. adjuste der 'andthe displacement or scavengin to thisend. I

ressure `to the inhalation precompresso -vand the distribution of the kh igh pressures. exist manner that while :they am @0I-filled t0v the high-pressure cylmfsdi) vtheir work-upon ,f

l i "specified inders and the .heatranges best-suited to'the pres# suresare localized in .each cylinder. For

' vantageous regenerative and heat sustaining for `.pecially eii'ective. in

` hottest part of .adopted in the case ofthe doub1e Se- ,l

thereof, but I1 desire tive and that theinvnticnf'caii l'the fourec'ycle operation and it *non en meenemen-@d a-compfesswn Stmk@ f .may be cited; the :'return as mechanical fstrolrefimeans-"for compressing the in'lpre-compresslon '.jincident'to and pres@ ent Withm'tlie'combustion'engine in sucha: u

\'ces sion' with the' air valve pistonv ofgvery.: large 'area'.` ain, by v'the rran'gementojthegroup `o i;

described, the Wall areas fordis-- j s runthe low-pressure cylinder 'T'witho Water jackets, whereby the Walls are maintained at a. medium 'high yet pract cable temperature., and an .available and adj function is thus secured in this cylinden'esf the latter .part of. the' Working stroke.

It will be seen -that each'end of eachig 1 the high pressure cylinders constitutes. in 1. g 1 connection with the chamber racticalljg,y

a combustion chamber .and as t isis-ther?.

the structure, the=va1ye2casj ing 13() 1s preferablyprovided conducted. valves 20, Fig. 5, whereby the expansion' the conneting hollow stem is. keptprac 5l tically uniform With that of thewallsofth valve casing, thus' maintaining a constan relation between the seats and l proper as the temperatures chang In accordance Withthe `provision patent statutes, l have herein describe rinciple ofj'operation of my invention gether with the apparatus which'` no l sider to represent' the best." embodi en to have-itfiunderstoo .g5-'f that ther apparatus shown only il lust ra-. ecarried;

out .b other means.t Also,Wliilejit,isI de-Q1 signe to use the various'- ieatnre'sand vele ments in the combination end`-relations scribed, sorne if/these may mafaltered an i101 Within 1-,heg mbustion cylinder, means for f .v utilizingth" urther expansion ofthe gases after :'tlieffl normal combustion or Working air, 'af'.

means for compressing -the .fuel

the' said combus- -i Sepers@ prior' to` introduction into tionfcylinder, n n air' valve opening into the combustion cylinder, and means for operating a `separate fuel valve, he valves in suc-A leading 4 the fuel 1201 valve inopening, as and for the purpose-v i '2;'v In@ `compound. four-cycle... interi'l'al combustionengine having vprior tofcombus j; tionan'inhalatlon and a'.compression strek' 125 'Within'the combustionV cylinder, means for- .1

L utilizing the. further expansion of the gases' y after they stroke, means for. compressing t normalgcombustion. or ,Workirxgl he"f air, a separate means for 'compressing rthe fueliac prior to introductioninto the said combustion cylinder, an air valve opening into the combustion cylinder, a fuel valve Vopening to the air valve, and means for opening the air valve previous to and closing it after the opening and closing of the fuel valve, for the purpose specified.

3. In a four-cycle, compound internal combustion engine, in combinatiolna low pressure cylinder, a pair of 'doubleacting high pressure cylinders operatively connected with the 10W pressure cylinder by suitable passages, pistons `for said cylinders, a common. crank shaft having a crank connected with the lov pressure piston, and a second crank connected to both of the high pressure pistons, and valves'for said cylinders timed so that the high pressure cylinders Will alternately exhaust into the lovv pressure cylinder at the tei'mination of the power stroke of the respective high pressure pistons.

4i. ln a four-cycle compound internal combustionengine, in combination, a low pressure cylinder, a pair of double'zwtingV high pressure cylinders .located one above the other and side by side and operatively connected with the low pressure cylinder by suitable passages,y pistons for said cylinders, a. crank shaft having a crank connected with i the low pressure piston, a common cross head 'for the high pressure pistons, a second crank on the crank shaft connected 'with `the cross head and displaced 180 from the first crank, aud'valves :tor said cylinders time(l se that the high pressu-rc cylinders will alternately exhaust into the low pressure cylinder.

In a four-cycle compound internal combustion engine, in combination, a double acting lowV pressure cylinder, a pair of double acting' high pressure cylinders operatively connected with the low pressure cylinder by suitable passages, pistons for said cylinders, a common crank shaft having cranks connected to the pistons, air, fuel and exhaust valves for the high pressure cylinders, exhaust valves for the low pressure cylinder, means for supplying' air and fuel under pressure to the high pressure cylinders, means. for ol'ieninpthe air valves durini! the exhaust ci the highpressure cylinders, and means for opening alternately the hipgh pressure cylinder exhaust valves which control the passage ol' the exhaust to the san'ieeud of the low pressure cylinder.

4(l. ln a fo11i--cycle compound internal combustion engine, in combination, a low pressure cylinder, a pair of high pressure cylinderslocated one above the other and Side by side and operatively connected with the ,low pressure cylinder by suitable passages,

pistons for said cylinders, a crank shaft having a crank connected with the low pressure piston, a common cross head tor the high valves of the highy pressure cylinders alternately.

4. In aA tour-cycle compound internal combustion engine, 1n combination, a loW pressure cylinder, a pair of double acting .high pressure cylinders located one above the other, side by side, and adjacent to and operatively connected with the low pressure cylinder by suitable passages, pistons for said cylinders, a common crank shaft having a crank connected with the low pressure pistons, and a second crank connected to both of the high pressure pistons, and valves for said cylinderstimed so that the high pressure cylinders will alternately begin to exhaust intothe low pressure cylinder at the terminations of the power strokes of the re spective high pressure pistons.

8. In a four-cycle compound combustion engine, the combination of a high pressure or combustion cylinder, a low pressure or expansion cylinder, the expansion cylinder having;` a. clearance space of minimum capacity and the combustion cylinder having a combustion chamber of such large capacity that ythe pressure therein will exceed atmospheric los open and for a period thereafter, andmeans for admitting-the gasesfrom the high pressure cylinder to the low 'pressure cylinder once during each cycle of operations.

9. ln a four-cycle combustion engine, the

combination with a cylinder and piston, of means for admitting fuel to the cylinder during; the inhalation stroke of the piston, a source et air under pressure, and' means for admittingl such air to the combustion chamber during the latter part et the eX haust stroke to scavenge the combustion chamber and 'also during; the inhalation stroke to mix with the fuel.

10. ln a four-cycle combustion engine, the combination with the cylinder and piston, of means for admitting fuel to the cylinder, a source of air under pressure, means for adV 'Initting such air to the combustion chamber before and aft-er the admission of' fuel'for the purpose of scavenging the combustion chamber and augmenting the charge therein, respectively, a low pressure or expansioncylinder, and means for admitting the gases from the high pressure cylinder to the low pressure cylinder once during each cycle of operations of the high pressure cylinder.

11. In a compound four-cycle combfistion engine having prior to combustion an inhalation and compression stroke Within the .combustion cylinder,a high pressure or combustion cylinder, ya. low pressure cylinder of larger displacement than the combustion '151 cylinder receiving the hot gases after.the normal Working stroke -Within the combustion cylinder, said combustioncylinder having a large clearance space of sufficient capacity for supplying pressure gases for both cylinders, means for introducing the constituents of the explosive charge into said combustion cylinder.and means for sepa- .rately compressing each constituent thereof toaJ pressure above the atmosphere prior to its delivery to the combustion cylinder.

12. In a four-cycle compound combustion engine, the combination of aligh pressure or combustion cylinder, a coupled low pressure orexpansion cylinder, the expansion cylinder having a clearance space of small capacity and the combustion cylinder having'a combustion space 'or chamber of relatively large capacity, the combustion chamber having a lateral extensionoverlapping the end of the low pressure cylinder and provided withva valved outlet leading di` rectly into said cylinder whereby dead space between the twofis avoided and the gases from the comb-ustion chamber may pass to the low pressure cylinder Without diminution in efficiency.

13. ln a four-cycle compound combustion' engine, the combination of two high. pressure Aor con'lbustion cylinders, a low pressure cylinder arranged adjacent to each of said -high pressure cylinders,combustion chambers forthe high pressurecylinders having laterally extending portions overlapping an end of the low pressure cylinder, and valve'd lopeningzgs between said combustion chambers uid the end of the low pressure cylinder, i 'ivhereby a direct transference of the gases from said combustionv chambers to the lowpressure cylinder Without diminution in eficiency is effected.

14.1n an internal combustion engine, in l-,combination,' a cylinder, a pistonworking therein, `air and, fuel inlet valves, Vindependent means for supplying the air and fuel 60 under different pressures, and a common means for controlling the relative pressures `of ithe air and fuel. .t 1,5. A four-cycle compound internal combustion-engine comprising, in combination, ($5A alpw pressure cylinder, a pair .of high pressure double actii'ig cylinders operativelyconnected with the lbiv pressure, cylinderby suitable passages, valve means lcontrolling the 'transfer of gases through said passages from the high pressure cylinders to the low ,f

pressure cylinder, pistons arranged to Workin said cylinders, an engine shaft, cranks on said shaft connected to said pistons, the high pressure and low pressure cranks being set substantially 180 degrees apart, and admission means for supplying air, and fuel to each high pressure cylinder on both sides of Vits piston, the operation of, said admission means and of the transfer-controlling valve means being so timed and correlated that' the high pressure cylinders exhaust alternately into the low pressure cylinder 16. A four-cycle co bustion engine compr a low pressure cylinder, ,pair of high pressure double acting cylinders opera. tively connected With the lovvpressure cylinder by suitable passages, valve meanscon-g trolling the transfer of passages from the high pressure cylinders to the lovv pressure'cylinder, pistons arranged to work in said cylinders, an engine shaft, cranks on said shaft lconnected to said pistons, the high pressure and low "pressure cranks being set substantially 180 degrees apart, admission valves arranged to deliver air and fuel near each end of each high pressure cylinder, means controlling said valves and double acting operation of said high pressure cylinders, said high pressure'cylinders being arranged to exhaust alternately into the low pressure iylinder through the connecting passages, and the transfer-controlling valve means beingarranged 'to maintain free communication between each high pressure cylinder andthe proper end of the low pressure cylinder substantially throughout an exhaust stroke in such high pressure cylinder.

17. ln a compound combustionl engine, the combination of high pressure and low Sil mpound internal -com-. isi'ng, in combination,

gases through vsaid 4 timed to give four-cycle 100 pressure cylinders and pistons,A a transfer r ,the combina-tion of high pressure and low valve between said cylinders located at the 'pressure' cylinders 'and pistons, a `double seated transfer valve betW'eensaid cylindersl and locatedA at` the end of the low pressure cylinder, and a forked plug on said low `valve seats, ivhereby the clearancein said piston '1s reduced to a minif pressure cylinder adapted to venter the transfer valve opening and straddle the stem' be- .tvveen jthe 19,1111 `a compound combustion engine,`

means for opening the intake valve during theflatter part of the exhaust stroke of the high pressure piston and while ythe transfer valve is open, whereby allot' the products of combustion in both the high pressure cyl- ,inderand said chamber are swept into the low pressure cylinder. i

2l).` ln a 'compound combustion engine, the combination with coupled high and low pressure cylinders and pistons, of an elonv.gated compression chamber connecting the ends of the two cylinders, a source of air under` pressure, an `air intake valve adjacent the high pressure end and a transfer valve adjacent lthe low pressure end of saidcham- .bel-Hand means for opening the said intake valve near the end' of the exhaust stroke ofthe high pressure piston and while the transfer vvalve is open', whereby scavenging air sweeps through said -high pressure cyl- ,inder and compression chamber and into said lw pressure cylinder.

Q1. In a compound combustion engine, the combination with coupled' high and low pressure cylinders and pistons, of an el0n gated compression chamber connecting the ends of the two cylinders, a source of air under pressure, air and fuel intake valves adjacent the high pressure end and a transfer vvalve adjacent the low pressure end of wsaid, chamberA and means for opening said airyalve near the end of 'the exhaust stroke ot the high pressure piston and while the transfer yalve is open, whereby scavenging air sweeps through said high pressure cyl inder `and compression chamber and into said low pressure cylinder.

y 32.` In a compound combustion engine, the combination with coupled high and low pressure cylinders and pistons, of an elongated compression chamber. connecting the endsof the two cylinders, a source of air under pressure, air and fuel intake valves adjacent the high pressure end and a transfer valve adjacent the lowv pressure end of said chamber and :means for opening said air valve prior to and closing .it after the fuel valve, the opening occurring during the latter part of the exhaust stroke. of the high pressure piston and while the transfer valve is open, whereby complete scavenging is effected. l

23. ln a compound combustion engine, the combination with coupled high and low pressure cylinders with their pistons, of an elongated compression chamber connecting the ends of the two cylinders, opening directly iu said high pressure cylinder, an intake ialvc `adjacent said high pressure end of said chamber and atransfer valve connecting said chamberand said low pressure cylinder, wherebyl a large clearance is provided for the high and a small clearance forV the `low pressure cylinder.

2l. In a compound combustion engine, the combination with coupled high and low pressure cylinders with their pistons, of an elongated compression chamber connecting the ends of the two cylinders, opening di rectly in saidhigh pressure cylinder, an intake valve adjacent said high pressureend of said chamber, a transfer valve connecting said cliambe and said low pressure cylinder, v

and a projection on the low pressure piston` adapted to enter the opening in the cylinder head formed by the passage to said transfer `valve, whereby a large clearance is provided for the high and a small cleaiance for the low pressure cylinder.

In a four-cycle combustion engine, the combination with the cylinder and piston, of means for admitting fuel to the cylinder during the inhalation stroke of the piston, a source of air under pressure, means for admitting such air to the combustion chamber before and after the admission of fuel for the purpose of scavenging the combustion chamber and augmenting the chargetherein, respectively, a low pressure or eX# pansion cylinder, and means for admittingv the gases from the high pressure cylinder to. the low pressure cylinder during the eX- haust stroke of the high pressure cylinder,`

while the air is being admitted and 'prior to the admission of the fuel.A

QG. In a four-cycle compound combustion engine, the combination of two high pres-v sure or combustion cylinders, a. low pressure cylinder arranged adjacent kboth of said high pressure cylinders, combustion cham-f bers for the high pressure cylinders hav-` ing laterally extending portions overlapC2 ping an end of the low pressure cylinder, valved openings between said combustion chambers and the'end of the low pressurecylinder, and projections on the low pres-V sure piston adapted to enter said openingsA to reduce clearances, whereby a direct transference of the gases from said combustion chambers to the low pressure cylinder with out diminution in ei'iiciency is effected.

Q7. ln an internal combustion engine, incoinbination, a cylinder, a piston working therein, air and fuel inlet valves, independent means for supplying the air and fuel under different pressures, and .means for controlling the relative pressures of the air and fuel lconriprising a storage tank for ,each fluid and af pressure equalizing connection between said tanks, adapted to maintainv the pressure of said fluids at any prew determined ratio.

28. In an internal combustion engine, the combination with a cylinder, a piston workias - fing' therein, y means for Asupplying at least one .-jffluitls undervariable pressure comprising a variable duty compressor and automatic- `-s'isting in varying 29.A In anl internal combustion aiizand fuel inlet valves, of of Athe means responsive to tlie eiigines speed for governing the., degree of compression coin the clearanoes.

combination with a working therein, air of means for supplying and fuel inlet valves, at least one of the ,o valves under variable 'pressure leon'iprising a variable duty compressor and automatic means responsive to the engines speed for governing tlie degree of compression,

30. ln an internal combustion engine, in combination, a eylinder, a piston working therein, air and fuel inlet valves, independent means for supplying the air under different pressures, equalizing tlie pressures between said indef pendent means, on a basisl of predetermined ratios. Y

3l. In an internal combustion engine, in combination, a cylinder, therein, air and fuel inlet valves, iiidepend entmeans for supplyingtlie airY and fuel under different pressures, and means for equalizing the pressures between said independent means on a basis of predetermined ratios and means whereby said ratios may be varied at will. l v ln an internal'combustion engine, in

combination, a cylinder, apiston working for supplying the therein, air and fuel inlet valves. indepeinlent means tionl of the engine, comprising a compressor fuel under pressure, and automatic means controlled by tlie engine speed for varying the operative clearance o said compressor.

33. Inan internal combustion engine, in combination, a cylinder, a vpiston working therein, air and fuel inlet valves, a eonnnon means for compressing without mixing botli the air and fr el, a eominon means for conand fuel, and independent 'trolling the relative pressures of the air means for supplying said air valve and said fuel valve its respective fiuid.

l`34a In an internal combustion engine, the combination with 'a eylinder and piston -working therein, air and fuel inlet valves,

engine, the cylinder Land piston and filet-means for governing and means foi` a piston working` ing tlierein and air 'means for governing for governing the fuel consunip- 4in, a fuel supply valve ivitli of means for supplying, at least one of the valves under variable pressure Comprising a variable duty compressor4 and automatic means responsive to tlie engines speed for governing the degree of compression, and for governing the lead of tlie spark.

35. In an internal combustion engine, the combination with a cylinder, a piston workingtherein and air and fuel inlet valves, of means for governing tlie fuel consumption lof tlie engine comprising a compressor for supplying at least one of tlie Combustion fluids under pressure and a common means for governing the degree of compression and the lopening of at least one of said valves.

256. In an internal' combustion engine, the combination with a cylinder, a piston working therein and air and fuel inlet valves, of `the fuel consumption of the engine, comprising two compressors for supplying the air and fuel independentlyT "and runder pressure, means for governing tlie degree ofeompression of both fiuids, and means working in syiielironism with said other governing means for governing the opening of said valves.

3T. n an interna-l combustion eiTgine, the combination ivitli a cylinder, a piston workand fuel inlet valves, of

the fuel consumption of tbe engine, comprising tivo compressors for supplying air and fuel independently and under pressure, means7 for equalixing the pressure of said air and fuel, means for governing the degree of compression of both fluids, and means ivorlv'ing in synclironisni with said Yother governing means for governing tlie 

